Mining machine bit



Feb. 26, 1946 5 H, GENTER 25395545 MINING MACHINE BIT Filed Aug. 2, 1944 IN VEN TOR.

WNW

Patented Feb. 26, 1946 UNITED STATES PATENT OFFICE MINING MACHINE BIT Albert H. Genter, Mount Lebanon, Pa. Application August 2, 1944, Serial No. 547,687

2 Claims.

This invention relates generally to cutting bits and more specifically to bits for use on endless chains of excavating or mining machines.

The principal objectof this invention is the provision of a replaceable bit having a plurality of cutting profiles formed within the dimensions of the stock of the bit.

Another object is the provision of a bit having a plurality of cutting profiles at each end thereof which are formed within th dimensions of the stock of the bit.

Another object is the provision of a straight shank bit having two teeth formed within the dimensions of the shank by a single grinding operation.

Another object is the provision of a straight shank bit having two teeth which are trihedral adjacent the apex with the intersecting sides forming the rake deviating to form a fourth side remote of the apex.

Another object is the provision of a bit the shank stock of which is rectangular in cross section and has a pair of cutting profiles the apices of which are at the corners of one edge of the shank.

Another object is the provision of a bit having an end face disposed at an acute angle to one edge of the bit and a V-groove defining the profile of two cutting teeth, which groove extends from the plane of the edge and runs out of the end face short of the other edge of the bit.

.Another object is the provision of a bit the shank of which is rectangular in cross section and having a hard metal surface along the side of shortest dimension with a V-groove cut through the hard metal into the end face of the shank providing two cutting profiles formed within the dimensions of the shank.

Other objects and advantages appear in the following description and claims.

Practical embodiments for illustrating the principles of this invention are shown on the accompanying drawing wherein:

Fig. 1 is a perspective view of a bit having the form of a parallelepiped.

Fig. 2. is a sectional view of the bit shown in Fig. 1.

Fig. 3 is an end view of the bit shown in Fig. 1.

Fig. 4 is a top plan view of the cuttingprofile of the bit.

Fig. 5 is a perspective view of a bit having the form of a solid trapezoid.

Referring to the drawing, the shank or body In of the bit is a metal bar preferably of rectangular cross section and of suitable length to be adjustably received in a socket of a continuous chain of an excavating or mining machine and to permit resharpening of the cutting profiles. The edge surfaces II and I2 are preferably in the proportion of three to eight relative to the side surfaces I3 and IA of the bit. In the form shown in Fig. 1 the end surfaces [5 and I6 of the bit are parallel and form acute angles with the edge surfaces H and I2 respectively. Thus the sides of this form are rhomboid and the solid is a parallelepiped.

Each end face 15 and I6 is provided with a V-groove l1 and I8 respectively. The bottoms of these grooves are substantially normal to the edge surfaces II and [2 respectively. Owing to the fact that the end faces I5 and I6 form an acute angle with the edge surfaces II and I2 and the bottoms of the V-grooves are substantially normal to these edge surfaces, the V-grooves run out of the end faces short of the opposite edge surface. The length of these grooves is approximately twice the width of the edge surfaces and the depth of the V-grooves in the edge surfaces is approximately equal to the width of said faces.

These V-grooves produce two cuting profiles on each end of the bit. The groove II forms the teeth l9 and 20 while the groove l8 forms the teeth 2| and 22.

When sharpened by grinding the grooves the teeth take the form of a four-sided pyramid and the apices are in alignment with the corners of the shank. Thus the teeth are pointed and within the dimensional extremities of the shank.

The edge surfaces II and I! are faced with cutting tool plates 23 and 24 such as a hard carbide which extend the life of these cutting profiles and the smaller double cutting profile has 1 more resistance to wear than a single profile. When the teeth atone end of the shank are worn the tool is reversed in the socket to employ the teeth on the other end.

The sides of the tool form shown in Fig. 5 are isosceles trapezoids in place of rhomboids as shown in Fig. 1. The teeth at one end are turned so that the single edge surface 25 provides the cutting profile of the teeth at both ends of the shank. In all other respects the tool of Fig. 5 is identical with the tool shown in Fig.

I claim: h

1. A bit for mining 'machines consisting of a straight shank having top, bottom and side surfaces, a face on the end of the shank disposed at an acute angle with the top surface of side surfaces, tat-face on the .end of the shank V disposed at an acute angle with the top surface of the shank, a V-groove in the end face of the shank intersecting the top surface and the side surfaces at the upper corners of the shank to define adjacent profile sides of two cutting teeth with their apices coincident with upper corners of the shank, the end face forming the rake of the teeth.

- ALBERT H. GENTER. 

